ID: 129
OBJECTID: 129
wlbNpdidWellbore: 131
wlbName: 25/2-8
wlbHistory:

General

The appraisal well 25/2-8 was drilled on the East Frigg Field. The main objectives of the well were to obtain a better estimation of the gas reserves on East Frigg and good pressure data in both the Frigg sand and the Paleocene sand. To achieve better knowledge about the petrophysical characteristics of the different reservoirs, it was decided to core the Frigg sand, the shaly member, the tuff zone and the Paleocene sand.

Operations and results

The well was spudded with the drill ship Le Pelerin on 18 June 1984 and drilled to TD at 2380 m in the Lower Paleocene Lista Formation. Problems due to tight hole occurred in the 12 1/4" hole section. The pipe got stuck at 1397 m, but was worked free. Problems pressure testing the BOP occurred with hole depth at 1745 m. A cement plug was set from 1000 m to 890 m due to the BOP problems. The core barrel was lost in the hole when pulling out of the hole with core no 9. The fish was recovered. The well was drilled using a water-based mud.

The Frigg sand was reached as prognosed at 1917.5 m. This formation is 283 m thick with a 48.5 m hydrocarbon bearing column: gas from 1917.5 m to 1957 m and oil from 1957 to 1966 m. Below this level was 18 m of residual oil. Shows were detected on cores and cuttings down to 2040 m. Balder formation (Paleocene) was reached at 2201 m with several Intra Balder Formation Sandstones. RFT pressure measurements in the Frigg sand and Intra Balder Formation Sandstone indicated that there is no direct fluid communication between the two formations. RFT segregated fluid samples were recovered from 2259 m in Intra Balder Formation Sandstone and at 1956.7 m and 1993 m in the Frigg Formation. The Intra Balder Formation Sandstone sample and the deeper Frigg sample recovered only water and mud filtrate and no gas, while the upper Frigg Sample recovered mud filtrate with traces of oil and about one litre of gas. Nine cores were cut, seven in the Eocene and two in
wlbHistoryDateUpdated: 2016-05-19T00:00:00